The invention relates to upgrading carbonaceous materials. In one aspect, the invention relates to the extraction of kerogen-containing materials. In another aspect, the invention relates to an apparatus for conducting an extraction process.
In one of its aspects, the invention relates to the treatment of oil shale to recover oil products. The heavy fraction of the crude shale oil normally contains a large fraction of high boiling components. This product is very viscous and difficult to handle and has such a high Conradson carbon content that upgrading is very expensive. A use for the heavy shale oil fraction which has a boiling point of above 1000.degree. F. would be desirable.
Many retorting processes cannot effectively process oil shale fines. These materials are usually rejected after the expense of transportation from the mine site to the shale conversion plant during screening operations. A process suitable for recovering oil from oil shale fines, especially fines having a size below 1/8 inch would be desirable.
Many pyrolysis processes for the extraction of shale oil from oil shale utilize partial combustion of the shale in a retort to provide the heat requirements of the pyrolysis process. Heat distribution through the retort is non-uniform, causing poor control over product distribution. The high temperatures in the combustion zone lead to over-cracking and metallurgical failures. Further, ecomomy of operation is hindered by heat dissipation due to excessively high combustor temperatures and poor heat transfer between the combustion gases and the shale. An oil yielding process which utilizes low temperature and improved temperature distribution would be desirable.